Detachable ladder and cage construction



Aug. 25, 1931. A. RAWSON DETACHABLE LADDER AND CAGE CONSTRUCTION 'Filed' Feb. 12 1929 w m D 4 T TOANEY i inventionrelates construction for derricks,

' vrick.

Patented Aug. 25,, 1931 L'Es'LIE A1 :imwsomor -Los ANGELEsoALIFOBNIA, ASSIGNOR 'ro Msco iDERRroKa E UIPMENT FOBNIA'L nm acnantnrnnnna Ann CAGE consrauc'rro'n t Application filed 'Feb ruary 12, 1929, Serial 1%.239508. f

to ladder and cage and one of the adf vantages of theinventionresides in the pros vision of ladder and cage structure adapted for detachable connection to any type ofderf Anoth e'r object ofthe invention is to provide for the complete elimination of bolts and nuts passing through'the derrick legsor the-reinforcing braces and substitutingtherefordetachable clamping means for connecting theladder and cage tothe derrick structure.

' volves quite f assembled or,

, rick structures,

, In the operation of drilling awell it is necessary to employ a relatively high derrick, and on the top of thederrick-in the ordinary apparatusiforinstalling and pulling thewell string. Inmodern oil-'field 'practic'e the derricks are of the fabricated type and maybe dismantled "at the well. It is frequently necessary forworkmen to go to the top of the ;leys on the crown block, and ordinarily iron ladders are riveted to theid'errick structure. This procedureinvolves the erection of lad- In the present invention the ladder and cage may be connected to the ordinary and well known types of derricks and he quickly detached therefrom for use in connection "with other derricks.

" A further ob ect of the invention istopro f derrlck structure may be of any desired type vide a ladderand cage structure of sectional orknock-down type whichis adapted for de-' tachable connection tov all derricks now use. The invention to be specifically described hereinafter is adaptable for use with any derbut is especially designed for use in 'connectlonflwith derricks' in the oil 'fields, though of course'it-may be readily used in connection in asimilar capacity 1flwillnow1descr tirely eliminatesthe above and other' disadwi'th- 011 gas-storage tanks ibe 'thestructure which avantages, reference being had to theaccompanying drawings in'which: I, v p

F g. 1 s apartlalslde elevatlonalviewof tion. Fig.

manner is located the crown block andoth'er derrick for repairsto the pul-' derrick, and likewise when they -'d errick 'is dismantled the ladders are :de- 1 Qtached from the derrick structure, which inan expense and extra work. 7

COMPANY, OFLOS Anonzcns, CALIFORNIA, A 'oonrona'rronor CALI- a pumping or a drilling derrick' provided with my improved ladder and cage construe proved ladder and cagecons'tructio'n illustrating partially its assembly.

, Fig. 3 is a sectionalvi'ew taken on line 83 of Fig. 2 showing the attachment of the cage to the derrick structure and, with aportion of the latter in elevation.

2 is a p'e'rspectiveview ofmyim" Flg, 4: 1s a seetlonal v1ew taken on lme 4- 4 of Fig. 2, and showing the connecting means I for the ladder to a supporting bar. I Fig. 5 1s a vertical sectional view taken through the cagesup'porting bars and illus trating one of the bolts for connectingthe ca e to the derrick structure. v

eferrmg to the drawings 'more in detail indicates the legs of any 'ordinaryder rick, the legs being formed in sections", as usual, and connected in-any desired manner', as by rivets. The means I have shown for bracing the legs comprises diagonalbraces 12, girt bars 13, and gussets l4, whichlatter connect the braces 12and girt bars ,131to the derricklegsld fl I r The base support and anchoring meansfor the derrick constitute'no particular part of the present invention. and in Fig. 1 I have therefore a merely indicated the conventional form of mounting, comprising thefconcrete pedestals15and 16 for thederrickand con- It may be understood that the body'ofthe crete pedestals 1 7 and 18supporting the end" housings 19 and 20. v

or construction, and .asth e particularconstruction the1-e0fforms no part of thefp'res-v entinvent on, the above description willi he sufficient.

of mountin the ladder andcageto,theside structure 0 (the derrick. Inprior-derrick constructionsthe ladder and cage structures have been fixed to the derits associated rickbody,'-so that they are immovable with l respect to the body without dismantling the derrick, or they may be removed from o V on the contrary, the invention relates broadly to a ladder and cage construction detachable with respect to the body, and it is to be under stood that the invention includes any and all means bywhich this may be accomplishec'l.

The ladder construction is indicated generally by the numeral 21, while the cage construction is indicated by the numeral 22.

The ladder construction comprises a series of ladder sections 23 of conventional form used in connection with'steel derricks but which in the past have been fixedly connected by horizontal supports to the derrick frame. Each ladder section 23 comprises side rails 24 and which are connected together in the usual manner by rounds 26. The number of the ladder sections and their associated cages employed, of course, depends entirely upon the height of the derrick to which they are to be attached, and likewise upon the number of rest and safety stops is indicated by the cagesnumbered generally as 22. The ladder sections 23 and ca -es 22 being each of similar construction,

(ml one unit comprising a ladder and a cage will be described.

Each ladder section 23 has connected to its side rails 24 and 25 by rivets 27, as illustrated in Fig. 4', the angle bars 28 and. 29 which have theirinner ends resting upon the upper horizontal leg of angle gi'rts 30 which may form one of the horizontal bars of the derrick, or which may be connected by bolts or rivets to the derrick legs 10.

The gifts 30 are Welded or bolted to the legs 10 of the derrick at intervals, though they are more particularly adapted for position between the cage systems 22. Extending downward throu h suitable openings in the angle bars 28 ancf 29 adj acent to the vertical leg 31 of an angle girt 30 are the hook bolts .32. Heads 33 of the hook bolts 32 are adapted to hook around a vertical leg 34 of the angle girt 30 and clam the parts together when nuts 35 on thread ed upper ends 36 of said bolts 32 are tightened against the angle bars 28 and 29. Connectedto, the derrick legs 10 and arranged in spaced relation throughout the-height of the derrick are angle girts 37 of identical construction to that of the intermediate angle girts 30. The angle girts 37 are arranged in pairs and are connected by rivets or bolts to the derrick legs 10, being adapted forsupporting the cage construction 22 in a manner as will now be described.

The cage construction 22 comprises horizontal angle rails 38 and 39, the inner ends of which are adapted to rest upon the hori- 7o zontal legs of the lower angle girt 37, which likewise may form one of the horizontal bars of the derrick. The outer ends of the rails 38 and 39 are riveted to upwardly and-inwardly inclined angle bars 40 and 41. The

:by bolts or rivets to the angle rails 38 and 39 and angle bars 40 and 41 in the following manner.

bars 44 and 45 connected at their lower ends to the outer ends of the rails 38 and 39, while the upper ends of the bars 44 and 45 are con nected to the angle bars 40 and 41 by bars 46 and 47 Cross-bars 48, 49, and 50 connect the upright bars 44 and 45 and provide a semienclosed landing at this point. p v

As heretofore stated the inner ends of the rails 38 and 39 rest upon the lower angle girt W 37, and for holding the same in position thereon I provide bolt hooks 51 clearly illustrated in Fig. 5. Thesehook bolts 51 extend downward from the rails 38 and 39 and'have heads 52 which hook around a vertical leg 53 of the angle girt 37, nuts 54being screwed upon 3 threaded ends 55 of said hook bolts 51, and when tightened serve to draw'the hook portions or heads 52 around the vertical leg 53 ofthe angle gift 37.

I The upper bent over ends 42 of the angle 5 bars 40 and 41 which rest upon the upper angle girt 37 carry hook bolts 56 and 57 of identically the same construction as the bolts 32 and 51 and are attached to the upper angle cage structures 22 are arranged side by side.

The cage structures as described provide transfer platforms for the workmen climb derrick by simply unscrewing the nuts 35" and 54. to provide for the removal of the hook bolts 32. 51, and 57.

lVhat I claim and desire to secure by Letters Patent is:

1. The combination with a derrick having The cage frame 43 comprises upright angle ea ins ins

ing the derrick, that is to say, the workmen a frame and angle girts of: ladder'sections,

cage sections surroundingthe-ends of said ladder sections; bars connected to said ladder sections and engaging said angle girts; bars connected to said cage sections and engaging said girts; and hook bolts carried by said bars and adapted for engagement With said girts for detachably supporting said sections upon said derrick frame.

2. The combination with a derrick having aframe and transverse girts of: a series of In testimony whereof, have hereunto set my hand at Los Angeles, California,'this; v-

4 day of February, 1929.

} ladder sections; cage sections surrounding V the ends of said ladder sectlons; angle bars to another; and hook members carried by said ladder and cage sections for detachably connecting said sections to said girts. p

4. The combination with a derrick having a frame including reinforcing girts of: a ladder section; a cage section surrounding an end of said ladder'section to provide a transfer platform therefor; and hook bolts carried by said ladder and-cage sections adapted for detachable connection to said girts;

5; The combination with a derrick having a frame including girts of: a ladder; bars secured to said ladder and being supported upon girts; and hookbolts carried bysaid bars and adapted" for engagement with said girts for detachably supporting said ladder onsaid derrick frame 6. The combination with a derrick frame including transverse girts of: a series of'laddersections adapted for attachment to said derrick; bars secured to said ladder sections 7 and being supported upon said girts;and

hook-elements carried by said bars and ene 1 gaging said girts for detachably clamping saidladder sections upon said derrick frame.

7. The combination with a'derrick frame including angle girts of: a ladder; bars, secured at one end to said ladder and having their opposite endssupported on said girts;

and hook members connected to the'free ends of said-bars and adapted to be hooked around said girts for detachably supporting said ladder upon said derrick frame.

8. The combination With a derrick frame including girts of: a ladder; angle bars secured to said ladder and being supported upon said girts; and hooks secured to said angle bars and adapted to be hooked around said girts for detachably. supporting said ladder thereon; v

LESLIE RAWSO-N. 

